The invention is based on an adjusting device as generally defined hereinafter. An adjusting device is already known in which the rotary motion of the electric motor is converted by a worm gear into a displacement movement of the actuating sleeve. This has the disadvantage that the worm gear cannot displace the actuating pin sufficiently accurately, and that because of the force exerted by the control device stop on the actuating pin, undesirably great frictional forces must be overcome in the worm gear by the electric motor.